This Biomedical Research Partnership project proposes to combine resources from professors of Mechanical Engineering and Physical Therapy through our newly organized Center for Biomedical Engineering Research at the University of Delaware. The five-year goal of this project is to assist patients with CNS dysfunction to produce improved walking patterns through a combination of functional electrical stimulation (FES), robotic-assistive training and biomechanical modeling. In the first phase of this project, which is described in this proposal, the focus will be on individuals with stroke exhibiting hemiparetic leg impairment. The technique should be generalizable to a variety of neurological impairments. The movements for these individuals will be improved or "optimized" in four ways: Nonrisk Maximize postural stability, Injury Minimize musculoskeletal injury (e.g., arthritis) during movement, Cosmesis Develop a more natural looking gait, and Energy Minimize metabolic energy consumption during movement. The "NICE" optimization protocol will be realized through musculoskeletal modeling, robotic assistance, functional electrical stimulation, and neuromuscular training. The specific task we will study will be partial body weight suspension gait on a treadmill. The organization of this project has been divided into 3 distinct aims, which may be summarized as follows. Aim 1: Identify impairments in the locomotor patterns of the lower extremity in patients with hemiparetic stroke and create a paradigm to optimize the movement patterns ("NICE" optimization). This will be accomplished through biomechanical modeling using gait analysis and electromyographic data. Aim 2: Develop the methods and equipment ("NICE" rehabilitation system) necessary to implements the "NICE" optimization of locomotion in patients with stroke. We will achieve this through the use of a robotic device and an electrical stimulation system. Aim 3: Test the feasibility of the use of the "NICE" rehabilitation system in patients with hemiparetic stroke and make adjustments to the system based on the patient trials. Our ten-year goal is to produce a portable (wearable) FES system to assist patients with CNS dysfunction in the production of coordinated movements.